CHIRAL INDUCTION IN NEMATICS - A COMPUTER-SIMULATION STUDY

We have studied chiral induction in a nematic in contact with a chiral surface using computer simulations. Nematic and surface particles hav e been modelled using the Gay-Berne (GB) potential considering, additi onally, a short-range chiral term for the inducing surface. We find th at, close to the chiral surface, a twist of the local director with re spect to the surface molecules is induced, even in the isotropic phase . In the nematic phase, the twist is maintained through orientational correlation and, even well inside, the sample molecules are effectivel y twisted with respect to the surface director. This process can highl ight the basic mechanism of the chiral induction of a cholesteric, i.e ., chiral nematic, phase. A detailed description of the molecular orga nization at various distances from the inducing surface is presented, using scalar and pseudoscalar orientational correlation functions.